public void destroy() {
        destoryTimer.cancel();
        destoryTimer = null;
    }

    @Override
    public boolean generate(final String thumbnailId, final File outputFile) {
        if (logger.isDebugEnabled()) {
            logger.debug("Generate Thumbnail: {}", thumbnailId);
        }

        if (outputFile.exists()) {
            if (logger.isDebugEnabled()) {